The present invention relates to a drill shear attachment for a portable hand drill, and more particularly to, drill shear attachment clamps for securing the shear attachment to the drill body to prevent shear attachment rotation and to permit one-handed operation of the drill with the shear attachment.
Building materials include metal panels, steel mesh, galvanized sheet metal, furnace jackets, spiral ducts, stone coated metal shingles and various types of corrugation metal panels. Panels that are also to be cut include automotive body panels for repair and replacement. U.S. Pat. No. 2,047,483 shows an example of electric shears which have begun to replace hand operated shears. U.S. Pat. No. 2,256,779 shows a shear attachment for a power drill unit. This attachment is quite cumbersome and not capable of navigating tight curves, patterns, or squares in heavy-duty gauge steel. U.S. Pat. No. 2,604,695 shows a hand-operated shear which has been used for decades to cut such metal sheets and panels. U.S. Pat. No. 2,635,335 shows a power driven hand-held sheet metal shears attachable to a drill with a one-way stabilizer that gives limited positioning of the attached metal shears. U.S. Pat. No. 3,654,700 shows a shear cutting head with a pair of movable jaws that supposedly does not cause the severed portion of the material to curl. U.S. Pat. No. 4,682,416 shows a metal cutting shear attachment securable to the collar of a portable drill.
Applicant's design U.S. Pat. No. D488,695 shows a simple drill shear attachment to a portable drill with a generally vertically oriented handle thereby requiring two-handed operation of the drill with the shear attachment.
There is a need for drill shear attachment clamps to secure a shear attachment to the chuck of portable drill as well as to the elongate drill body for single-handed operations in either the right side up or upside down orientation.